Laws for Pat Yisroel and Chalav Yisroel

Is one required to keep Pat Yisroel and Chalav Yisroel only in Israel? I live in an area that some people actually ship in food from the East Coast to keep these laws, however doing so requires great sacrifice financially. We keep Glatt kosher and kosher by the Union of Orthodox Rabbis in the U.S., but our goal is to see that our children are able to attend full time religious school as long as we can afford it.

Answer

BS"D
Shalom and Bircat Hashem!
The prohibitions concerning Pat Yisrael and Chalav Yisrael are binding everywhere and there is no difference between Eretz Yisrael and the Diaspora. However, it is easier in Eretz Yisrael to be strict in such matters.
The Achronim were in disagreement in cases where the laws of the country prohibit adultering [kosher] milk with non-kosher milk, and impose monetary fines on violators: should we still be wary [and prohibit consumption of Chalav Akum] or not? The Igrot Moshe (Yoreh Deah, Part I, Siman 47) is of the opinion to be lenient and definitively rule that this is not a case of Halav Akum, [that the situation is] as if [Jews] witnessed the milking, however the Igrot Moshe also points out that there is reason for those particularly sensitive about Halacha to be strict on this matter even if it necessitates a slight [additional] expenditure. It appears that HaGaon Rav Moshe Feinstein ZTZ"L ruled that there is no need to incur great expense in order to drink Chalav Yisrael when regular milk is produced under the authority of the state which ensures than it is not adulterated by non-kosher milk. However, there were those who disagreed and ruled that one must be strict in all matters. Therefore, it seems that initially (Lechatchila) it is worthwhile for those particularly sensitive about halacha to drink only Chalav Yisrael, but if this is a very great expense one may be lenient and drink Chalav Akum that is under governmental supervision, especially if in the country in which the milk is milked there is no non-kosher milk or if it is more expensive than regular milk. In that case those particularly sensitive to halacha may also drink [Chalav Akum]. Let me specify that all of this concerns milk itself, and that concerning milk powder produced from Chalav Akum one may be more lenient, especially if it is in a mixture such as with chocolate and chocolate products. In this case it is possible to allow [products containing Chalav Akum] when purchasing products containing Chalav Yisrael necessitates large expenditures.
Pat Nocrim is prohibited, although there were places where bread was purchased from non-Jewish bakeries, but not from individual non-Jews, when Pat Yisrael was unavailable. Because bread is a more vital food than milk there were those who were more lenient concerning Pat Akum than they were concerning Chalav Akum. In any event it is obvious that in a place where there is Pat Yisrael one may not purchase Pat Akum. However, in a place where there is only Pat Nochri (from a bakery) one may be lenient when [purchasing Pat Yisrael] necessitates great expenditure and inconvenience. If there is a suspicion that prohibited ingredients have been added to the bread then there is no cause for leniency.
We are required to make efforts to obtain permissible foods, however we emphasize instilling in our children the love of Torah and educating them to proper, upstanding Middot.
Sincerely,
HaRav Yehuda HaLevi Amichai